Reaktion #926604

ord-534efe0925824e2dae91070e5941e854

Reaktionsgleichung

O=C([O-])[O-].[Na+].[Na+]
sodium carbonate
CCOC(=O)/C=C\C(=O)[O-]
monoethyl maleate
NNc1ccc(S(=O)(=O)[O-])cc1
p-hydrazinobenzene sulphonate
O=C([O-])[O-].[Na+].[Na+]
sodium carbonate
Cl
hydrochloric acid
→
O=C(O)C1CC(=O)N(c2ccc(S(=O)(=O)O)cc2)N1
3carboxy-1-(4'-sulphophenyl)-5-pyrazolidone
Ausbeute 76.0%

Edukte

O=C([O-])[O-].[Na+].[Na+]
sodium carbonate
CCOC(=O)/C=C\C(=O)[O-]
monoethyl maleate
NNc1ccc(S(=O)(=O)[O-])cc1
p-hydrazinobenzene sulphonate
O=C([O-])[O-].[Na+].[Na+]
sodium carbonate
Cl
hydrochloric acid

Reagenzien

Keine

Lösungsmittel

O
water

Reaktionsbedingungen

Temperatur
100°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Vorschrift

2 parts of monoethyl maleate are added with stirring to 25 parts of water containing 2 parts of p-hydrazinobenzene sulphonate and 1 part of sodium carbonate. The mixture is heated at 100° C for 5 hours. The resulting solution is warmed with sodium carbonate and the pH finally adjusted to 3-4 with hydrochloric acid. The 3carboxy-1-(4'-sulphophenyl)-5-pyrazolidone thus formed is filtered off and dried between 50°-100° C. The actual weight yield is 4 parts of strength 74% (determined by N.M.R.) which represents a yield of 76%.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US04095024uspto-grants-1978_06